Fig. 2

a Patient with a pelvic mass for whom RECIST is an adequate measure of tumor burden, and volumetric measurement provides little additional information. At the most recent follow-up appointment, RECIST indicated a partial response (–43.9 %) and volume indicated a minor response (–59.9 %). b Volumetric measurement of the patient’s primary lesion. c Six months later, the tumor had shrunk by both RECIST and volume